you could also try xattr -cr "/Applications/Octodad Dadliest Catch.app"
I am unable to fix this at this time. I updated our app to fix all the issues that the mac app store said needed fixing to be on their store and still no luck). It seems to be a common problem with itch and mac os (see bottom here): https://itch.io/docs/itch/integrating/platforms/macos.html
Their solution is to install the itch client (which I tested and runs fine and does not have the problem). If you cannot get xattr method to work I suggest downloading the itch client here: https://itch.io/app and installing that way. If you then want to uninstall itch but keep Octoadad you can copy the Octodad Dadliest Catch.app to Applications or any other folder by clicking on the settings icon in the itch client next to launch then -> Manage -> Show in Finder